Process of making charcoal and apparatus therefor.



7 S1 I'WAMOTO. I PROCESS OFMAKING CHARCOAL Ami APP'ARATUS THEREFOR.

APPLICATION FILED AUQZB. Qfh v 7' I Patented May 22, 19171 gwumrfoz 2 shin -shin 1.

v 502770 /wamo7"o S. IWAMOTO. PROCESS OF MAKING CHARCOAL AND APPARATUS THEREFOR.

APPLICATION FILED AUG-28. I915,

Patented May 22,1917.

2 SHEETS-SHEET 2.

,0 6 y d d r IIIIIII r|||||| agg wil'ncoo SUMU IWAMOTO, 0F HIGASHI-KU, OSAKA, JAPAN.

PROCESS OF MAKING CHARCOAL AND .APPARATI J'S THEREFOR.

Specification of Letters Patent.

Patented May 22, 1917;

Application filed August 28, 1915. Serial No. 47,864. I

To all whom it may concern:

Be it known that ITSUMU IWAMo'ro, citizen of Japan, residing at No. 20 Awajimachi, Itchome, Higashi-Ku, Osaka, J apan,

to which it appertains to make and use the same.

This invention relates to the manufacture of charcoal; and it comprises a process wherein wood or the like is carbonized in a suitable kiln or retort, with recovery. of byproducts, and the carbonized wood is then further and more intensely heated by admitting air into the retort to effect partial combustion of said carbonized wood, the resultant charcoal being most desirably removed from the retort while hot. and then quickly cooled. The invention further comprises appariatus for carrying out the process aforesai Heretofore charcoal has been produced by either of two principal methods. .According to one ofthese, wood is charred by direct contact with flame and hot combustion gases, part of the wood being burned to furnish the heat required for conversion of'the rest into charcoal. As the method is practised. in Japan, the treating kiln has no separate combustion chamber, but is provided with what may be termed a ventilation hole or flue, known in Japan as daishi-ana, which, in conjunction with dampered hot air flues, permits admission of preheated air into the kiln when the wood has been sufficiently carbonized, whereby the carbonized wood is given a final intense heating to a red heat. This intense heating renders the charcoal hard and dense; and although this method has the disadvantage that the valuable byproducts go to waste, nevertheless the superior character of the charcoal produced thereby is wellrecognized.

According to the second or by-product method, the wood to be charred is heated in closed retorts out of contact with air, combustion gases, etc., and the'volatile products distilled ad from the wood, such as acetic acid and wood alcohol, are recovered in well known ways. As heretofore practised,however, this method has produced an inferior grade of charcoal which is so brittle and porous as to have comparatively little value as a fuel. a v

The primary object of the present inven tion is to attain the desirable results of both methods referred to while avoiding the.

drawbacks to whichboth are subject; in-

other words, to recover the by-products of wood distillation, and also to produce a high grade'charcoal of the quality peculiar to-the J apanese method described.

Briefly described, the new method consists in first distilling wood with recovery of the valuable volatile matters driven OE, and then hardening and densifying the residualchar by an intense final heating effected by combustion of a part of the char itself. To this end a novel type of apparatus. is employed, comprising a kiln or retort in which the wood is placed and which isarranged to be indirectly heated by means of flues located in the kiln walls and adapted to receive flame and hot combustion gases from a suitable combustion chamber. The kiln is also provided with a ventilation hole or daishi-ana and dampered air-admission pipes connecting with the flues aforesaid, whereby, after, the distillation proper has proceeded far enough, preheated air may be introduced 1nto the kiln to efi'ect partial combustion of the charred wood and the desired final heat- 7 ing up of the product.

The invention will be more fully under- I stood by reference to the accompanying drawings, in which:

Figure 1 is a front view of a kiln in which the process may be carried out, the view being partly in section on the line c-d of Fig. 3; I

Fig. 2 is a plan view of Fig. 1;

Fig. 3 1s a horizontal section on the line e-f-m-bof'Fig. 1;

Fig. 4 is a vertical section on the line g-h of Fig. 1; and

Fig. 5 is a "vertical section on the line P3 of Fig. 1.

Referring to the drawings, 1 designates{ generally a klln constructed of refractory material such as stone for example. In the present example, the kiln is shown as comprising a pair of retort chambers in a unitary construction. At the front are provided doors lthrough which charcoal, materials, such as wood, can be charged into the" retort chambers. Vapor pipes or conduits 3 are adapted to convey products of distillation from the retort chamber andto conduct the same to a place of recovery. Leading from the lower part of each retort chamber at the rear and passing upwardly in the rear Wall is the ventilation hole or passage known in Japan as the daishi-ana. This ventilation passage is extended upwardly through conduit 5 which intersects the vapor pipe 3 as shown and extends therebeyOnd to any convenient point of discharge.

he vapor pipe 3 is provided with dampers 6 and 7 on opposite sides of the ventilation passage 5; while the latter is provided with a damper 8 above thepoint of'intersection. On both sides and in the middle of the kiln are located combustion chambers 9, 10 and 11 which heat the retorts. These chambers are located slightly below the level of the "retort floors and are provided with doors 9', 10, 11' and 9', 10", (not shown) and 11 for fuel-feeding and draft purposes. Communicating with the combustion chambers are flues 12, 13 and 14 which extend horizontally from the chambers toward the back wall of the kiln. The side flues 13 and 14 lead to rear flues 15' and 15, respectively; while the center flue 12 branches off to right and left into rear flues of which only one, flue 16, is here shown. The four flues 15, 15, 16 and the flue on the other side corresponding to 16 curve upwardly into flues l7, 1?,18 and 18, respectively. Flues 17 and 17 leadinto flues 19 and 19', respectively, which are located in the upper part of the side walls above flues l3 and 14;;

while flues 18 and 18 unite in fiue 20 which lies above the lower middle flue 12. Flues 19, 19 and 20 lead from the rear of the kiln forwardly into chimneys or stacks 23, 22 and 21 respectively, dampers 23, 22' and 21 being provided for the several chimneys as shown. The front ends of flues 19, 19 and 20 are connected to the retort chambers proper by means of pipes 24, 25, 26 and 27, as shown.

In the present example, the flue. system below the retort chambers may comprise flues 28 and 28leading from the central combustion chamber 9 toward the front of the kiln, and then. passing rearwardly in the form of several parallel flues to the tines 16 and 16. Similarly flue 29 curves for wardly from combustion chamber 10 and then branches into flue 15 at the rear. A similar arrangement (not shown) is provided for combustion chamber 11.

In carrying out the new method with the described apparatus, the retort chambers are first charged with wood or similar materials through the doors 2 which are then closed tightly. The chimney dampers 21, 22 and 23 being closed, and hot air dampers 24', 25, 26' and 27 being open, fires are started in the combustion chambersfi, 1G and 11. The flames and hot combustion gases pass rearwardly through flues 12, 13

being incombustible,'raise the temperature within the retorts quickly and intensely without any flaming. As soon as the temperature of the materials in the 'retorts reaches the point where decomposition is about to begin, the dampers 24, 25, 26, and 27 are closed and the chimney dampers 21', 22' and 23' are opened. The hot combustion gases cannot .enter the retorts under these conditions, and said retorts are now heated indirectly byconduction through the retort walls. vThe valuable volatile products of distillation are led off from the retorts through the vapor pipes 3, the dampers 6 and 7 being open and damper 8 being closed.

When the distillation has been continued to a suflicient extent to properly carbonize the materials in the retort chambers, the

fires in the combustion chambers 9, 10 and 11 are discontinued. Chimney dampers 21, 22' and 23 are now closed; and hot .air dampers 24, 25, 26 and 27 are opened; while dampers 6 and 7 are closed and damper 8 is opened. All the doors of the combustion chambers are then opened to admit air which passes through the intensely hot flues and thence into the retort chambers through pipes 24, 25, 26 and 27'. The in troduction of this highly heated air into the retort chambers produces a partial combustion of the charcoal therein and heats the main bulk thereof to an intense red heat. This hardens and densifics the charcoal as before explained. When the proper degree of hardening is attained, the charcoal is raked out of the kiln while still hot and is buried in ashes so as to cool it quickly. The charcoal resulting from this process, unlike charcoal cooled insidethe kiln, is very solid and compact- While a specific example of the novel process and apparatus has been described for the sake of a clear disclosure, it is to be understood that the invention is not limited to the exact details, specified.

What I claim is:

1. The process of making charcoal which comprises carbonizing wood by indirect heating, then further heating the carbon ized wood by direct flame, and finally cooling the resultant charcoal.

2. The process of making charcoal which comprises carbonizing wood by indirect heating'and recevering distillation products,

effecting partial combustion thereof, and

. tort indirectly,

I finally cooling the resultant charcoal. 9

.3. The process of making charcoal which comprises distilling and carbonizing wood in a suitable kiln by indlrect heating, then admitting air to the retort to effect combustion of a part of the carbonized wood and to densify the remainder, removing the charcoal from the kiln while still highly heated, and cooling the charcoal quickly.

4:. A charcoal kiln comprising a woodcharring retort, means for heating said remeans for leading ofi distillation products from said retortto a place of recovery, means for admitting air to said retort for combustion purposes, and means for leading off combustion products therefrom. 1 v

5. A charcoal kiln charring retort, a system of heating fines in a wall of the retort, a combustion chamber arranged to supply heat to such flue system,

a conduit for leadmgoif distillation prodflues into the retort chamber, tion hole or passage through which gases amaly escape from the retort chamber.

n testimony whereof Ivhereunto affix my comprising a wood-' ucts from said retort, a conduit affording commumcatlon betweensaid flue system and the interior of the retort, a conduit for leading oif combustion products from the retort,

and controlling dampers for the several conduits.

'6. A charcoal kiln comprising a retort chamber, a ductfor leading off distillation products therefrom, a furnace arranged somewhat lower than the floor of the retort chamber, fiues leading from said furnace along the side walls and underneath the floor of the retort chamber, a chimney into which said flues may conduct gases, conduit means whereby gases may pass from said and-a ventilasignature in the presence of two witnesses.

. SUMU IWAMOTO.

Witnesses:

W. EBIHABAT,

Ionnzo LUDZAEKI. 

